Super PAC officials earlier in the day filed documents with the FEC for a new group, Rebuilding America Now, that Barrack said had attracted tens of millions of dollars in early money. Barrack, who hosted Trump's first major fundraiser, has long been pointed to by donors as an eventual point man for Trump's super PAC operation, which thus far is nascent and has yet to attract large donations. He said he will not have a formal role with the group.

About four donors account for the $32 million, Barrack told CNN. These include new donors who have never donated large amounts of money to the Republican Party before. It took five phone calls to woo the donors, Barrack said, who he declined to identify.

Barrack said the principal operatives behind the group are Ken McKay and Laurie Gay. McKay, the former campaign manager to New Jersey Gov. Chris Christie, is currently a senior adviser to Trump's campaign and would be required by election law to "cool off" from the campaign before aiding an outside group.

Gay is an ally of Paul Manafort, Trump's chief strategist and one power center in Trump's cadre of aides. The treasurer for the group is Ryan Call, a former chair of the Colorado Republican Party.

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"These super PACs have meaning, they have purpose, but they have been viewed historically as being not so trustworthy," Barrack said on "OutFront." "So the idea of having a solid, trustworthy -- with no skimming, no float -- that's aligned with the candidate but is not coordinating with the candidate, is key."

Major donors have skeptically viewed the first two super PACs that have flooded the pro-Trump space, with questions raised about their viability and operational effectiveness. One of the original groups, Great America PAC, is about to begin a series of five kickoff fundraisers, including a multi-day event in Dallas next weekend, according to lead donor Bill Doddridge.

Great America PAC was defiant Thursday despite the news of a better-funded rival.

"It's not surprising to see the emergence of new super PACs supporting Donald Trump, and some may recruit top level donors like we have already done," said Eric Beach, a strategist for the group. "But the bottom line is we are way ahead of everyone else. Our approach is unique and will be highly effective."

The close ties between this Trump group and the official campaign could assuage concerns from wealthy donors about where to place their funds. Trump sharply disavowed super PACs during his primary campaign, but his campaign has been largely silent about the independent groups that have begun fundraising for the general election.

Trump nevertheless is expected to be significantly outspent by Hillary Clinton and her allied groups.

Trump himself has started traditional fundraising, and Barrack also reflected on the finance event he hosted in Los Angeles on his behalf, which raised a total of $9.5 million -- $3.5 million of which came after the event. Barrack said Trump was at ease before the crowd.

"He was amazing. He was funny. He was charming. He was totally indulged in the individuality of the crowd," Barrack said. "He was his real, usual class act."